<title>查找大于等于x的最小元素</title><link href="http://hzoi.com/tomorrow.css" rel="stylesheet"><div class="ui existing segment"><pre><code><span class="pl-cp">#include</span><span class="pl-cpf">&lt;cstdio&gt;</span><span class="pl-cp"></span>
<span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-mi">100005</span><span class="pl-p">]</span><span class="pl-o">=</span><span class="pl-p">{</span><span class="pl-mi">0</span><span class="pl-p">};</span>
<span class="pl-kt">int</span>  <span class="pl-nf">main</span><span class="pl-p">(){</span>
	<span class="pl-n">freopen</span><span class="pl-p">(</span><span class="pl-s">&quot;findmin.in&quot;</span><span class="pl-p">,</span><span class="pl-s">&quot;r&quot;</span><span class="pl-p">,</span><span class="pl-n">stdin</span><span class="pl-p">);</span>
	<span class="pl-n">freopen</span><span class="pl-p">(</span><span class="pl-s">&quot;findmin.out&quot;</span><span class="pl-p">,</span><span class="pl-s">&quot;w&quot;</span><span class="pl-p">,</span><span class="pl-n">stdout</span><span class="pl-p">);</span>
	<span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">n</span><span class="pl-p">;</span>
	<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%lld&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">n</span><span class="pl-p">);</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-mi">0</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&lt;</span><span class="pl-n">n</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
		<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%lld&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]);</span>
	<span class="pl-p">}</span>
	
	<span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">m</span><span class="pl-p">;</span>
	<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%lld&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">m</span><span class="pl-p">);</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-mi">0</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&lt;</span><span class="pl-n">m</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
		<span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">c</span><span class="pl-p">;</span>
		<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%lld&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">c</span><span class="pl-p">);</span>
		<span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">l</span><span class="pl-o">=</span><span class="pl-mi">0</span><span class="pl-p">,</span><span class="pl-n">r</span><span class="pl-o">=</span><span class="pl-n">n</span><span class="pl-o">-</span><span class="pl-mi">1</span><span class="pl-p">,</span><span class="pl-n">mid</span><span class="pl-p">;</span>
		<span class="pl-n">mid</span><span class="pl-o">=</span><span class="pl-n">l</span><span class="pl-o">+</span><span class="pl-p">(</span><span class="pl-n">r</span><span class="pl-o">-</span><span class="pl-n">l</span><span class="pl-p">)</span><span class="pl-o">/</span><span class="pl-mi">2</span><span class="pl-p">;</span>
		<span class="pl-k">while</span><span class="pl-p">(</span><span class="pl-n">l</span><span class="pl-o">&lt;</span><span class="pl-n">r</span><span class="pl-o">-</span><span class="pl-mi">1</span><span class="pl-p">){</span>
			<span class="pl-c1">//mid=(r+l)/2;</span>
			<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">mid</span><span class="pl-p">]</span><span class="pl-o">&lt;</span><span class="pl-n">c</span><span class="pl-p">){</span>
				<span class="pl-c1">//printf(&quot;mid:%lld l:%lld r:%lld\n&quot;,mid,l,r);</span>
				<span class="pl-n">l</span><span class="pl-o">=</span><span class="pl-n">mid</span><span class="pl-p">;</span>
			<span class="pl-p">}</span>
			<span class="pl-k">else</span> <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">mid</span><span class="pl-p">]</span><span class="pl-o">&gt;=</span><span class="pl-n">c</span><span class="pl-p">){</span>
				<span class="pl-c1">//printf(&quot;mid:%lld l:%lld r:%lld\n&quot;,mid,l,r);</span>
				<span class="pl-n">r</span><span class="pl-o">=</span><span class="pl-n">mid</span><span class="pl-p">;</span>
			<span class="pl-p">}</span>
			<span class="pl-k">else</span><span class="pl-p">{</span>
				<span class="pl-k">break</span><span class="pl-p">;</span>
			<span class="pl-p">}</span>
			<span class="pl-n">mid</span><span class="pl-o">=</span><span class="pl-n">l</span><span class="pl-o">+</span><span class="pl-p">(</span><span class="pl-n">r</span><span class="pl-o">-</span><span class="pl-n">l</span><span class="pl-p">)</span><span class="pl-o">/</span><span class="pl-mi">2</span><span class="pl-p">;</span>
		<span class="pl-p">}</span>
		<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">mid</span><span class="pl-o">+</span><span class="pl-mi">1</span><span class="pl-p">]</span><span class="pl-o">&lt;</span><span class="pl-n">c</span><span class="pl-p">)</span><span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;-1</span><span class="pl-se">\n</span><span class="pl-s">&quot;</span><span class="pl-p">);</span>
		<span class="pl-k">else</span> <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">mid</span><span class="pl-p">]</span><span class="pl-o">&gt;=</span><span class="pl-n">c</span><span class="pl-p">)</span><span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;%lld</span><span class="pl-se">\n</span><span class="pl-s">&quot;</span><span class="pl-p">,</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">mid</span><span class="pl-p">]);</span>
		<span class="pl-k">else</span> <span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;%lld</span><span class="pl-se">\n</span><span class="pl-s">&quot;</span><span class="pl-p">,</span><span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">mid</span><span class="pl-o">+</span><span class="pl-mi">1</span><span class="pl-p">]);</span>
	<span class="pl-p">}</span>
	<span class="pl-k">return</span> <span class="pl-mi">0</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
</cpde></pre></div>